The use of chemical herbicides for the control of phytopathogenic fungi is environmentally undesirable, hence the search for a more eco-friendly approach. This research is intended to determine the inhibitory potential of Heteropogon contortus (L.) Buauv, on some phytopathogenic fungi. Soil samples from fifty (50) farmlands in Ethiope east Local Government Area of Delta State, were aseptically collected and assessed for the presence of phytopathogenic fungi. By serial dilution, spread plate technique, cultural characteristics as well as microscopic examination, Fusarium sp., Alternaria sp. and Aspergillus sp. were isolated in percentage occurrences of 34%, 42%, and 64% respectively. Fresh leaves of Heteropogon contortus (L.) buauv were collected, rinsed in running water and air dried and then grounded to fine powder, which was extracted using methanol and water. Phytochemicals recovered included; Flavonoids, Alkaloids, Tannins, Phenols, Terpenoids, and Saponins. Poisoned plate technique was used for percentage inhibition of fungal mycelia growth using the aqueous extract, after three and five days. Alternaria sp. had a 100% inhibition, at days three and five, using a concentration of 7µL/mL and 5µL/ respectively. Aspergillus sp. exhibited a 100% mycelia inhibition at days three and five, using concentrations of 5µL/mL and 3µL/mL respectively. Fusarium sp. on the other hand, had a 100% mycelia inhibition at days three and five, using concentrations of 8µL/mL and 6µL/mL respectively. This study reveals inhibition of the phytopathogenic fungi and this inhibition increases with increasing concentrations and period of exposure. Spear grass may prove useful after all as an inhibitor of phytopathogenic fungi.
